The invention relates to a heat exchanger for an exchange of heat between a first fluid and a second fluid, having: a block for the separate and heat-exchanging guidance of the first and second fluids, which block has a number of flow ducts which can be traversed by the first fluid and a housing which holds the flow ducts and which can be traversed by the second fluid; at least one casing cover which is flow-connected to the flow ducts, a base which is fixed to the casing cover and which is provided with one or with a plurality of passage openings for flow ducts. The invention also relates to a use of the heat exchanger.
In a known heat exchanger, a tank cover may be formed from deep-drawn sheet metal which is soldered to the block during the production process. Although this has advantages in the high-temperature range, add-on components such as for example brackets or flanges for sensors must be produced as additional parts from sheet metal and connected to the tank cover before the soldering process, which makes the production process more complicated. Furthermore, a more complex tank shape can generally no longer be produced as a deep-drawn part, such that, in this case, production must take place by means of casting, and the tank cover must generally be welded to the block. Said type of tank has proven to be comparatively expensive and complex to produce specifically in the case of more complex structural shapes.
One cost-effective alternative to heat exchangers of said type is a heat exchanger of the type specified in the introduction, in which the tank has a tank cover composed of plastic. Here, it is possible to realize comparatively complex structural shapes, with it being by all means possible, with corresponding plastic materials and a corresponding design of the tank, to also realize higher temperature ranges. Examples of tank covers composed of plastic are specified in DE 10 2004 051 207 A1 and DE 10 2004 047 901 A1.
There are fundamentally different ways of attaching a plastic tank cover to the heat exchanger, such as for example connections as shown in WO 2004/09457, FIG. 2 or DE 199 53 785 A1, FIG. 4.
DE 10 2005 012 761 A1 discloses a heat exchanger of the type specified in the introduction, having a housing composed of two side parts and two housing covers, with the side parts being soldered to the block and the housing cover being welded to the side parts. Furthermore, collecting tanks composed of plastic are mechanically connected, with the interposition of a seal, to tube plates. The mechanical connection is achieved by bending lugs of the tube plates over the edge of the collecting tank. Said type of heat exchanger has room for improvement.
What is desirable is a design of a heat exchanger which is comparatively simple to produce and in which it is nevertheless possible to realize comparatively complex structural shapes. This relates in particular to the design of a base of the heat exchanger.
What is also desirable is a further advantageously improved connection of a tank cover, in particular of a tank cover composed of a non-metallic material, to a metal part, to the base of a heat exchanger, preferably so as to provide an improved sealing action. Also desirable is an improvement to a housing of the heat exchanger.